api docs: Document the get-streams endpoint.

This commit documents the get-streams endpoint, which can be
by making a GET request to /api/v1/streams.

Note that in the code examples, JavaScript is missing an example
for how to pass in the `include_` query parameters. That is
because zulip-js's client.streams.retrieve function doesn't take
any arguments and zulip-js does not export any function equivalent
to client.call_endpoint in python-zulip-api/zulip.

templates/zerver/api/arguments.json

@@ -44,5 +44,31 @@
             "required":"Required",
             "example":"Hello"
         }
+    ],
+    "get-all-streams.md":[
+        {
+            "argument":"include_public",
+            "description":"Include all public streams. Default is `True`.",
+            "required":"Optional",
+            "example":"`True` or `False`"
+        },
+        {
+            "argument":"include_subscribed",
+            "description":"Include all streams that the user is subscribed to. Default is `True`.",
+            "required":"Optional",
+            "example":"`True` or `False`"
+        },
+        {
+            "argument":"include_all_active",
+            "description":"Include all active streams. The user must have administrative privileges to use this parameter. Default is `False`.",
+            "required":"Optional",
+            "example":"`True` or `False`"
+        },
+        {
+            "argument":"include_default",
+            "description":"Include all default streams for the user's realm. Default is `False`.",
+            "required":"Optional",
+            "example":"`True` or `False`"
+        }
     ]
 }

templates/zerver/api/get-all-streams.md

@@ -0,0 +1,150 @@
+# Get all streams
+
+Get all streams that the user has access to.
+
+`GET {{ api_url }}/v1/streams`
+
+## Arguments
+
+**Note**: The following arguments are all URL query parameters.
+
+{generate_api_arguments_table|arguments.json|get-all-streams.md}
+
+## Usage examples
+<div class="code-section" markdown="1">
+<ul class="nav">
+<li data-language="curl">curl</li>
+<li data-language="python">Python</li>
+<li data-language="javascript">JavaScript</li>
+</ul>
+<div class="blocks">
+
+<div data-language="curl" markdown="1">
+
+```
+curl {{ api_url }}/v1/streams -u BOT_EMAIL_ADDRESS:BOT_API_KEY
+```
+
+You may pass in one or more of the parameters mentioned above
+as URL query parameters, like so:
+
+```
+curl {{ api_url }}/v1/streams?include_public=false \
+    -u BOT_EMAIL_ADDRESS:BOT_API_KEY
+```
+
+</div>
+
+<div data-language="python" markdown="1">
+
+```
+#!/usr/bin/env python
+
+import zulip
+import sys
+
+# Keyword arguments 'email' and 'api_key' are not required if you are using ~/.zuliprc
+client = zulip.Client(email="othello-bot@example.com",
+                      api_key="a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5",
+                      site="{{ api_url }}")
+
+# Get all streams that the user has access to
+print(client.get_streams())
+
+# You may pass in one or more of the query parameters mentioned above
+# as keyword arguments, like so:
+print(client.get_streams(include_public=False))
+```
+
+</div>
+
+<div data-language="javascript" markdown="1">
+More examples and documentation can be found [here](https://github.com/zulip/zulip-js).
+```js
+const zulip = require('zulip-js');
+
+const config = {
+  username: 'othello-bot@example.com',
+  apiKey: 'a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5',
+  realm: '{{ api_url }}'
+};
+
+const client = zulip(config);
+
+// Get all streams that the user has access to
+client.streams.retrieve().then(res => {
+    console.log(res);
+});
+
+```
+</div>
+
+</div>
+
+</div>
+
+## Response
+
+#### Return values
+
+* `stream_id`: The unique ID of a stream.
+* `name`: The name of a stream.
+* `description`: A short description of a stream.
+* `invite-only`: Specifies whether a stream is invite-only or not.
+  Only people who have been invited can access an invite-only stream.
+
+#### Example response
+
+A typical successful JSON response may look like:
+
+```
+{
+    'result':'success',
+    'streams':[
+        {
+            'stream_id':15,
+            'name':'Denmark',
+            'invite_only':False,
+            'description':'A Scandinavian country'
+        },
+        {
+            'stream_id':16,
+            'name':'Rome',
+            'invite_only':False,
+            'description':'Yet another Italian city'
+        },
+        {
+            'stream_id':17,
+            'name':'Scotland',
+            'invite_only':False,
+            'description':'Located in the United Kingdom'
+        },
+        {
+            'stream_id':18,
+            'name':'Venice',
+            'invite_only':False,
+            'description':'A northeastern Italian city'
+        },
+        {
+            'stream_id':19,
+            'name':'Verona',
+            'invite_only':False,
+            'description':'A city in Italy'
+        }
+    ],
+    'msg':''
+}
+```
+
+An example of a JSON response for when the user is not authorized
+to use the `include_all_active` parameter:
+
+```
+{
+    'code':'BAD_REQUEST',
+    'result':'error',
+    'msg':'User not authorized for this query'
+}
+```
+
+{!invalid-api-key-json-response.md!}

templates/zerver/api/sidebar.md

@@ -8,6 +8,10 @@
 * [Stream message](/api/stream-message)
 * [Private message](/api/private-message)
 
+#### Streams
+
+* [Get all streams](/api/get-all-streams)
+
 ## Integrations
 
 * [Overview](/api/integration-guide)